NEW YORK (Reuters Health) - Follow-up of patients with intrahepatic cholestasis of pregnancy (ICP) may be necessary because of an increased risk of subsequent hepatobiliary disease, according to a report in the April issue of Hepatology.

Previous studies have noted an association of ICP with gallstones and hepatitis C, the authors explain, but there are no reports describing a link between ICP and the risk of liver or biliary diseases.

Dr. Anne Ropponen from Helsinki University Central Hospital, Finland and colleagues used the Finnish Hospital Discharge Register to investigate the occurrence of liver and biliary diseases in more than 21,000 women with ICP and in a similar number of matched controls from the general population.

ICP was associated with an increased incidence of hepatitis C and nonspecific hepatitis, including autoimmune hepatitis, the authors report, but not with the development of hepatitis A or hepatitis B.

Women with ICP also faced a higher risk of developing nonalcoholic cirrhosis with liver fibrosis, primary biliary cirrhosis, and miscellaneous liver disorders. In contrast, the results indicate, ICP was not associated with alcohol-related liver disorders or diseases of bilirubin metabolism.

Cholecystitis, cholelithiasis, and other biliary system disorders occurred with greater frequency in women with ICP, the researchers note, as did nonalcoholic pancreatitis.

"The etiology of ICP remains unknown and the cause of its association with other diseases is also presently unknown," the investigators write. "It is possible that some diseases increase the risk of ICP or that there is a common cause for ICP and some other liver and biliary diseases."

"These results suggest that in a subgroup of patients ICP may not be solely a self-limiting, spontaneously resolving condition, but also an indicator of subsequent, often more serious diseases," the authors conclude. "To resolve the nature of the association we have identified, further studies are clearly indicated."